By Bryan Geyer
 |
| Bob Widlar, the Genesis |
When partners Sony
and Philips initially teamed to develop the compact disc (1979) and the first
CDs came to market (in early 1983, in the U.S.), the unveiling was widely
hailed as the arrival of “perfect sound forever”. That infamous quote
has long been derided by persistent doubters, and there have been plenty of
hiccups en route, but much of the best unbiased opinion of today concludes that
the Sony/Philips claim was effectively prescient, although premature. Assuming
good playback mechanics and modern decoding technology, standard Red Book CDs
are now aurally indistinguishable from the finest high resolution means of
digital recording extant. While a select set of audiophiles might still dispute
that opinion, and contend that some favored hi-rez digital streaming process
presents audible advantage, their collective criticism has shriveled. Today,
with obviously increasing consistency, dedicated audio connoisseurs concur
that, finally, there’s little or no detectable difference between standard Red
Book CD audio quality and the best of the other alternatives. Any aural quality
gap, if such exists at all, is now too trifling to merit recognition when it
comes to human perception.
What accounts for
this evolutionary improvement in CD sound quality? Well, just as in the case of
so many other things, there’s likely no one single reason. It’s probably the
culmination of a lot of learning, adjustment, and adaptation—plus dramatic
improvement the accuracy of the monolithic integrated circuit chips that
comprise all modern digital-to-analog converters (DACs). Here’s my take…
Listening habits…
When CDs were
initially introduced, listeners were quick to appreciate the improvement in
background noise, but many didn’t know how to handle the enhanced dynamic range
to best advantage. This certainly happened to me! In 1987, I already owned an
LP recording of the original Perlman/Giulini
performance of the Beethoven Violin Concerto, and when I compared it to
the new CD release of the same performance, I judged the CD sound to be
inferior; it seemed subdued. I later realized that this was because I had
listened at about the same peak volume levels as set for the LP record.
When I later advanced the volume to boost the quiet passages of the CD to
more nearly match the LP’s quiet parts, the CD sound came alive; the enhanced
dynamic range was then apparent. It took me a while to adjust to this asset.
Even today, I think that lots of listeners persist in setting “sub-natural” CD
volume levels. This tendency is further driven by the compulsion to reduce the
listening level when bombarded by pop-market CDs that are mastered with
compressed peaks (to yield consistently loud sound). That’s a stunt that can’t
be done when mastering to vinyl, and might account for the vinyl preference
that some listeners profess when they compare a popular LP record with its CD
equivalent. Thankfully, this intentional compression of the signal is confined
exclusively to the making of “pop market” CDs, where the “mobile market”
dominates, and where loud equates with better. Classical music
CDs have never been mis-mastered in this same corrupt manner.
Learning curve
priorities…
Early phase CDs that
trace to the mid/late 1980s were often inconsistent. Mixing and mastering techniques
were in flux, and conversion accuracy didn’t meet what’s available today*.
Progressive improvements in recording technology evolved throughout the mid-’90s
and into the ensuing decade, buoyed by improved methods of test and
measurement. This progress was probably slowed by the attendant clamor to
create higher density storage when emphasis was diverted to focus on various
forms of compression, e.g. MP3 (1993) + its derivatives (1995, 1998, 2008).
Regardless, the decisions and commitments that Sony and Philips made in the
beginning have ultimately proved correct. Forty year foresight in the field of
consumer technology is rare, but these two companies were uniquely capable,
with superb engineering staffs, visionary management, and a strength of conviction
seldom seen in corporate environs. It’s accurate to say that what they promised
has been achieved.
Conversion
accuracy…
Major advances in
monolithic semiconductor manufacture, especially with respect to the “on board”
integration of symmetrical differential linear topology, has progressively
boosted the performance of audio frequency DAC chips. Designs that were once considered challenging are now churned out on bigger wafers, with better test yields. These current generation chips can provide
standard Red Book CD sound quality that’s fully consistent with the limits of
human perception, and do so at costs that make it feasible to use them in a
wide variety of consumer-level gear. Their application in the high performance
audio products market has been pervasive in the course of the recent decade.
CD access…
While it’s convenient
to access CD quality via Tidal streaming, that means is somewhat better suited
to popular music. Cloud shopping for classical selections can get complex; maybe
even messy. Your personal nature, and the music genre involved, will largely
decide how you elect to build your own private music library. My overwhelming
preference is to buy and own the physical CD, rather than pay for periodic
access. I vastly prefer having the disc in hand. But I always listen only at
home—I’m not into mobile listening—and I utilize headphones only in the
bedroom, and only for audio books.
Those who express
serious interest in playing CDs at home will need a good player and a modern
DAC. The latter can be either self-contained, inside the CD transport, or
provided as a separate external box. Top quality converters are available both
ways, and an external DAC isn’t inherently superior. In my experience, “good”
CD players start in the vicinity of ~ $1,500 and go upward. The cheaper players
are just not consistently reliable. A really good CD player should provide long
problem-free service life, smooth and responsive control options, quiet
operation, and a relatively modern DAC. Stick to single disc players. There are
no existing multi-disc CD players that I can personally recommend at this time,
and the play time (to 80 minutes max.) of a CD is such that one-at-a-time
feeding is appropriate. Use an FM tuner source if you want background fill.
Used CD players are obviously high risk, and they might not utilize a modern
DAC.
The vinyl
alternative…
…is a grossly
inferior substitute. Refer…https://classicalcandor.blogspot.com/2019/07/on-considering-vinyl-revival.html.
*Monolithic operational amplifiers have become a vital component in the evolution of high performance DACs. The world’s first op amp chips (µA702, µA709) appeared in the mid-1960s, as devised by linear design genius Bob Widlar, a brilliant eccentric who was then at Fairchild Semiconductor. Intensive development and improvement followed throughout the 1970s and into the mid-’80s. Later emphasis was devoted to advances in symmetrical integration, shrinking topology, increases in wafer size, and yield enhancement. All of the high performance DACs made today utilize this late phase linear technology. The level of excellence that’s been achieved in the past 15 years exceeds anything previously envisioned, and current OEM selling prices make these op amp chips practical for use in almost any consumer market electronic product.
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